[test] Fix unstable test CommitLakeTableSnapshotITCase.testCommitDataLakeData (apache#867)

Author: wuchong

fluss-server/src/test/java/com/alibaba/fluss/server/replica/CommitLakeTableSnapshotITCase.java

@@ -83,6 +83,7 @@ void testCommitDataLakeData() throws Exception {
             int leaderServer = FLUSS_CLUSTER_EXTENSION.waitAndGetLeader(tb);
             TabletServerGateway leaderGateWay =
                     FLUSS_CLUSTER_EXTENSION.newTabletServerClientForNode(leaderServer);
+            FLUSS_CLUSTER_EXTENSION.waitUtilAllReplicaReady(tb);
 
             for (int i = 0; i < 10; i++) {
                 leaderGateWay